The river's headwaters form on the north slope of Nestor Peak.
He discovered it while leading an expedition, consisting of 25 men and 45 horses, through this area of the Rocky Mountains in 1841.
Trail blazing faster shorter routes to the jointly occupied region which the British called the Columbia District and American's referred to as Oregon Country, was essential if the British were to hold it.
A trail blaze with his initials, was found in 1904 atop Simpson Pass, near present-day Sunshine Village.
This article related to a river in the Interior of British Columbia, Canada is a stub.